Engineering Commons^™

Distributed Multichannel Speech Enhancement Based On Perceptually-Motivated Bayesian Estimators Of The Spectral Amplitude, Marek B. Trawicki, Michael T. Johnson

Electrical and Computer Engineering Faculty Research and Publications

In this study, the authors propose multichannel weighted Euclidean (WE) and weighted cosh (WCOSH) cost function estimators for speech enhancement in the distributed microphone scenario. The goal of the work is to illustrate the advantages of utilising additional microphones and modified cost functions for improving signal-to-noise ratio (SNR) and segmental SNR (SSNR) along with log-likelihood ratio (LLR) and perceptual evaluation of speech quality (PESQ) objective metrics over the corresponding single-channel baseline estimators. As with their single-channel counterparts, the perceptually-motivated multichannel WE and WCOSH estimators are functions of a weighting law parameter, which influences attention of the noisy spectral amplitude through …

Market Analysis For Small And Mid-Size Commercial Turboprop Aircraft, Vitaly S. Guzhva, Tamilla Curtis, Vladislav Borodulin

Publications

Recent fuel price volatility and growing concerns about the efficiency of regional jets have led to a revival of large turboprop aircraft as efficient passenger carriers on short-haul regional routes. However, the overall market for smaller turboprops is much less defined as it is characterized by a plethora of small commuter and niche operators in addition to regional carriers. Since most small and mid-size turboprop manufacturers have gone bankrupt or discontinued production due to some other reasons, current operators of this aircraft class are left with aging fleets that would need to be replaced by 2020-2030. This paper assesses the …

Inquiry-Guided Learning (Igl) In Graphical Communications Course, Lulu Sun, Christopher Grant

Publications

Inquiry-Guided Learning (IGL) is an active learning technique which promotes students critical thinking through guided independent investigation of complex problems without a single solution, which has been studied and implemented by many researchers in science and engineering fields [1-8]. It is believed that IGL can provide an opportunity to the students to explore their desires and consequently enhance students’ learning experience in the classroom. Graphical Communications, as a common course taught at first-year undergraduate level at Embry-Riddle Aeronautical University is designed to familiarize the student with the basic principles of drafting and engineering drawing, to improve three dimensional visualization skills, …

Extra-Matrix Mg2+ Limits Ca2+ Uptake And Modulates Ca2+ Uptake-Independent Respiration And Redox State In Cardiac Isolated Mitochondria, Age D. Boelens, Ranjan K. Pradhan, Christoph A. Blomeyer, Amadou K.S. Camara, Ranjan K. Dash, David F. Stowe

Biomedical Engineering Faculty Research and Publications

Cardiac mitochondrial matrix (m) free Ca²⁺ ([Ca²⁺]_m) increases primarily by Ca²⁺ uptake through the Ca²⁺ uniporter (CU). Ca²⁺ uptake via the CU is attenuated by extra-matrix (e) Mg²⁺ ([Mg²⁺]_e). How [Ca²⁺]_m is dynamically modulated by interacting physiological levels of [Ca²⁺]_e and [Mg²⁺]_e and how this interaction alters bioenergetics are not well understood. We postulated that as [Mg²⁺]_e modulates Ca²⁺ uptake via the CU, it also alters bioenergetics in a matrix Ca²⁺–induced and …

Design For The Asce Steel Bridge Competition, James Behel, Silvia Garcia, Reyn Kimura, Scott Nowak

Civil, Environmental and Sustainable Engineering Senior Theses

On April 20, 2013, the Santa Clara University Steel Bridge Team entered in the American Society of Civil Engineers' (ASCE) National Student Steel Bridge Competition. As part of their senior design, the four member team designed and constructed a steel bridge to compete in the annual competition. Engineering senior design projects require thoughtful planning, execution, and documentation throughout the process. The 2013 team approach was to be proactive and aggressive in all aspects of the project. The 2013 Steel Bridge spanned 16.5 ft and had a 3.5 ft cantilever end. The overall dimensions of the bridge for its height and …

An Approach To Light-Frame Disaster Relief Housing, Hayley Dickson, Megan Cronan, Anne Walkingshaw, Katherine Busch

Civil, Environmental and Sustainable Engineering Senior Theses

An Approach to Light-Frame Disaster Relief Housing investigated the use of bamboo structures to provide safe, affordable and easily constructible housing in developing countries that are prone to natural disasters. The team chose to use the Cagayan Valley Region in Northern Philippines that has a demonstrated need for relief housing due to its susceptibility to high seismic activity, monsoons, and floods. The proposed solution includes a complete structural and geotechnical foundation design of a house that can resist the demand loads determined for the region. The structural system is designed using bamboo and includes a lateral force resisting system, and …

Organic Solar Cells Based On High Dielectric Constant Materials: An Approach To Increase Efficiency, Khalil Jumah Tawfiq Hamam

Dissertations

The efficiency of organic solar cells still lags behind inorganic solar cells due to their low dielectric constant which results in a weakly screened columbic attraction between the photogenerated electron-hole system, therefore the probability of charge separating is low. Having an organic material with a high dielectric constant could be the solution to get separated charges or at least weakly bounded electron-hole pairs. Therefore, high dielectric constant materials have been investigated and studied by measuring modified metal-phthalocyanine (MePc) and polyaniline in pellets and thin films. The dielectric constant was investigated as a function of temperature and frequency in the range …

Global Skin Friction Diagnostics: The Glof Technique And Measurements Of Complex Separated Flows, Sudesh A. Woodiga

Dissertations

This work describes the application of the global luminescent oil film skin friction meter to quantitative global skin friction diagnostics of complex separated flows. The development of this technique is based on the relationship between the oil film thickness and luminescent intensity of a luminescent oil film. The projected thin oil film equation is given to relate the normalized luminescent intensity with skin friction. The variational formulation with a smoothness constraint on skin friction is proposed to obtain a snap shot solution from two consecutive images for a relative skin friction field. A complete skin friction field is reconstructed through …

Evaluation Of Novel High-Density Emg Feedback Parameters On The Spatial Distribution Of Trapezius Muscle Activity, Brecca M. Gaffney

Electronic Theses and Dissertations

Each year, 17.9% of adults working in a computer-dominated work environment develop an episode of chronic neck and shoulder pain. An effective treatment method for chronic pain is postural correction through therapist. The understanding of the relation between cervicoscapular posture and trapezius muscle activity is not fully understood because the anatomy of the scapula is not accessible for direct observation. Until recently, the spatial distribution of trapezius muscle activity could not be measured due to the limitation in size of detection zone in traditional bipolar electrodes. The primary goal of postural correction when treating cases of chronic neck and shoulder …

Adaptive Data Acquisition For Communication Networks, Behzad Ahmadi

Dissertations

In an increasing number of communication systems, such as sensor networks or local area networks within medical, financial or military institutions, nodes communicate information sources (e.g., video, audio) over multiple hops. Moreover, nodes have, or can acquire, correlated information sources from the environment, e.g., from data bases or from measurements. Among the new design problems raised by the outlined scenarios, two key issues are addressed in this dissertation: 1) How to preserve the consistency of sensitive information across multiple hops; 2) How to incorporate the design of actuation in the form of data acquisition and network probing in the optimization …

An Innovative Protective Jacket For Structures Subject To Blast Loads: A Comprehensive Experimental And Simulation Study, Nicholas J. Carlson

Dissertations

As the importance of protective engineering and multi-hazard mitigation design has grown in recent years, the development of an effective structural protection system that aids in the preservation of life safety during blast events is an important topic of research in structural engineering. This protection is especially vital for blast and explosion mitigation, where a vehicle-borne bomb or an improvised explosive device can readily cause an under-designed structure with insufficient redundancy to undergo progressive collapse due to the removal of its first-floor columns. An especially pressing research need is the consideration of structures that require blast protection, but—due to time …

Enabling Sustainable Power Distribution Networks By Using Smart Grid Communications, Chun-Hao Lo

Dissertations

Smart grid modernization enables integration of computing, information and communications capabilities into the legacy electric power grid system, especially the low voltage distribution networks where various consumers are located. The evolutionary paradigm has initiated worldwide deployment of an enormous number of smart meters as well as renewable energy sources at end-user levels. The future distribution networks as part of advanced metering infrastructure (AMI) will involve decentralized power control operations under associated smart grid communications networks. This dissertation addresses three potential problems anticipated in the future distribution networks of smart grid: 1) local power congestion due to power surpluses produced by …

Developing Crash Modification Factors For Operational Parameters On Urban Freeways, Eugene Vida Maina

Dissertations

Studies have shown that, roadway safety has become an intensively investigated topic with the objective of improved understanding of the factors that cause crashes to occur. However, it has been shown that as traffic volumes continue to increase across the United States, 52% of drivers feel less safe on the roads today more than they did five years ago and that the American public feels that traffic safety is a serious problem that needs both the government and media to pay more attention to this issue.

In response to these public and driver grievances, State and National transportation agencies have …

The Effect Of Nanoclays On The Properties Of Aspirin Modified Enteric Polymer Prepared By Hot-Melt Mixing, Nonjaros Chomcharn

Dissertations

Melt mixing in batch equipment or continuous extruders is a technique that recently gained the attention of the pharmaceutical industry. This dissertation investigates two controlled-release drug delivery systems. The first system, namely the enteric matrix, contains an active pharmaceutical ingredient (API) and plasticizer in an enteric polymer while in the second system a nanoclay is added to the enteric matrix, to produce a polymer nanocomposite. The first system employs hot-melt mixing to prepare a modified enteric matrix, as a delayed-release dosage form. Different concentrations of aspirin (ASP) ranging from 10 – 30% w/w are melt-mixed with a plasticized Eudragit® …

High Performance Digital Signal Processing: Theory, Design, And Applications In Finance, Mustafa Ugur Torun

Dissertations

The way scientific research and business is conducted has drastically changed over the last decade. Big data and data-intensive scientific discovery are two terms that have been coined recently. They describe the tremendous amounts of noisy data, created extremely rapidly by various sensing devices and methods that need to be explored for information inference. Researchers and practitioners who can obtain meaningful information out of big data in the shortest time gain a competitive advantage. Hence, there is more need than ever for a variety of high performance computational tools for scientific and business analytics. Interest in developing efficient data processing …

Influence Of Sinx/Si Interface States On Si Solar Cells, Santosh Sahoo

Dissertations

Impact of the SiN_x/n⁺-Si interface on silicon solar cell performance was investigated, where SiN_x is used as a passivation layer. Significant shifts in capacitance, conductance and leakage current characteristics were observed for metal/SiN:H/n⁺-Si MOS capacitor when it was subjected to a constant voltage stress (CVS) of +10V at room temperature. The interface trap density (D_it) across the SiN:H/n⁺-Si interface increased from 6.3 x 10⁹ to 7.5 x 10⁹ cm^-2 eV^-1 after a 500-second stress whereas the n⁺/p junction diode remained unaffected by the …

Hosx: Hospital Operations Excellence Model, Shivon S. Boodhoo

Dissertations

Hospital performance can be evaluated in four categories: (i) quality of care, (ii) process of care (iii) financial and (iv) operations productivity. Of these, ‘quality of care’ is the most widely reported and studied measure of performance, and focuses primarily on the clinical outcomes of the patient. In contrast, operations productivity and efficiency is the least studied measure, and currently there is limited ability to evaluate how efficiently the hospital has used its resources to deliver healthcare services. Cost containment in the healthcare industry is a challenging problem, and there is a lack of models and methods to benchmark hospital …

Synthesis And Characterization Of Novel Boron-Based Nanostructures And Composites, Rajen B. Patel

Dissertations

A number of nanomaterials have been synthesized by using a method that has been previously utilized to make pure boron nanostructures through the addition of different reactant gases to the process. This method was pioneered by Iqbal-Liu and will be referred to as the IL method in this dissertation. The IL method successfully created boron nanowires, boron nanoflakes, and boron nanotubes. In this dissertation, by adding methane, hydrogen sulfide, and ammonia to the process, an entire family of nanomaterials is prepared. These include nanowires, nano-heterostructures, and thin nanoplatelets of a variety of elemental compositions. These materials can be integrated with …

Reaction Mechanisms Of Hydrocarbon And Mercury Systems In The Atmosphere And In Combustion: A Theoretical Study Of Thermochemical And Kinetic Properties, Itsaso Auzmendi Murua

Dissertations

The continuing increase in the world population and the rapidly changing lifestyle and education of this population projects significant increases in energy requirements. Global warming is a worldwide major concern with a very serious potential stress on our climate threatening major changes to the environment. It is, without question, of major importance to improve the efficiency and optimize the current available combustion processes and fuel sources, to develop alternative fuels and to reduce the emissions of toxic pollutants.

The objective of this dissertation is to present thermochemical, kinetic and modeling results on two reference fuels (the land vehicle fuel isooctane …

The Effects Of Rapid Stretch Injury On Rat Neocortical Cultures, George Constandinos Magou

Dissertations

Several key biological mechanisms of traumatic injury to axons have been elucidated using in vitro stretch injury models. These models, however, are based on the experimentation of single cultures keeping productivity slow. Indeed, low yield has hindered important and well founded investigations requiring high throughput methods such as proteomic analyses. To meet this need, a multi-well high throughput injury device is engineered to accelerate and accommodate the next generation of traumatic brain injury research. This modular system stretch-injures neuronal cultures in either a 24-well culture plate format or six individual wells simultaneously. Custom software control allows the user to accurately …

Foaming Of Amorphous Drug Delivery Systems Prepared By Hot Melt Mixing And Extrusion, Graciela Terife

Dissertations

Currently there is considerable interest from both academe and pharmaceutical industry in exploring foaming processes and their products in drug delivery applications. However, there is still little knowledge of the impact of the morphology of the foamed structures on the performance of drug products in spite of some publications in this area. Therefore, the main objective of this dissertation is to gain a fundamental understanding of the correlation between foam morphology and performance of amorphous drug delivery systems, which are comprised of an Active Pharmaceutical Ingredient (API) and Polymer excipient.

The Hot Melt Extrusion (HME) process is used to compound …

Metal Based Reactive Nanocomposites Prepared By Cryomilling, Shasha Zhang

Dissertations

Aluminum is one of the most commonly used metal fuel additives for propellants, explosives, and pyrotechnics. Recent interest has been focused on replacements for aluminum as fuel additives to achieve higher combustion temperatures and stronger pressure pulses for applications in advanced munitions systems. Two applications are addressed in this work. In the applications for explosives designed to defeat stockpiles of chemical and biological weapons, it is of interest to develop multifunctional materials combining the high energy density of metal fuels with the biocidal activity of halogens. A challenge of this effort is to design and prepare powder-like Al-I2 materials which …

End-To-End Network Measurement For Wired And Wireless Networks, Khondaker Musfakus Salehin

Dissertations

A number of Internet applications require accurate characterization of different network parameters. There is, therefore, a need to determine whether the networks that carry packets for those applications comply with the requirements. Network measurement provides the means to perform this determination. This work focuses on schemes for measuring several parameters both in wired and wireless environments.

The need of measuring packet processing time (PPT) of the end hosts (i.e., workstations) in a wired network is unveiled. PPT is defined as the time elapsed between the arrival of a packet at the data-link layer and the time when the packet is …

Senior Design Theses: Moving To An Electronic Collection By Collaborating With The School Of Engineering, Susan K. Boyd

Staff publications, research, and presentations

For years, the University Library served as a literal “storage room” for the latest ten years of printed senior design or capstone theses. Both the receiving and cataloging of student undergraduate work were at best “spotty,” and incomplete. By working with the Associate Dean of Undergraduate Studies, and departmental administrative assistants, the library and the School of Engineering developed a new process for electronic submission of these documents, and this in turn resulted in the creation of the University Library’s institutional repository called “Scholar Commons.” The first collection within Scholar Commons will showcase the senior design theses. To inform students …

Production Of Stable Bcs Class Ii Drug Suspensions By Melt Emulsification And Subsequent Incorporation Into Polymer Strip Films, Emanuel Joseph Vizzotti

Theses

One of the ways to improve the dissolution rate of poorly water-soluble drugs is to produce fine drug particles with increased surface area. This increase will lead to bioavailability enhancement. However, smaller drug particles are thermodynamically unstable and tend to aggregate or grow. Therefore, proper formulation and process parameters must be chosen to keep the particles small. In this study, fine drug particles of two model drugs, fenofibrate and ibuprofen, are prepared by the melt emulsification technique. The influence of suspension formulation (i.e., the inclusion of polymers and surface-active agents) on particle stability is investigated. Moreover, different agitation techniques during …

Heterogeneous Combustion Of Condensed Particles In Transition Regime, Deniz Yildiz

Theses

A steady-state model of heterogeneous combustion for a spherical particle is developed accounting for the transition regime of heat and mass transfer. The model assumes formation of condensed products and reaction rate controlled by the transport of oxidizer to the particle surface. The model is based on the Fuchs’ limiting sphere approach. Calculations are performed for combustion of zirconium particles of different sizes. Temperature and oxygen concentration profiles are calculated and compared to those predicted by the continuous medium transfer model. It is shown that for particles in the range from 100 nm up to 30 gm heat and mass …

Hollow Fiber Membrane-Based Air Gap Membrane Distillation, Xuan Wang

Theses

Membrane Distillation (MD) is a thermally-driven separation process. In this research, desalination of 1 % NaCl solution is achieved by one type of MD namely, Air Gap Membrane Distillation (AGMD). The characteristics of AGMD are evaluated by using a hollow-fiber-set-based compact device. Hot brine solution and cold water are passed through two different fiber sets separately: porous hydrophobic polyvinylidene fluoride hollow fibers of the E type (PVDF E) and solid polypropylene (PP) hollow fibers. Vapor from the hot brine crosses the membrane pores of the PVDF fibers and the air gap, and finally condenses over the surface of solid hollow …

Finite Element Modeling Of Temperature Elevation Due To Nir Exposure In Neural Tissue, Atabek Can Yucel

Theses

Near infrared (NIR) lasers have been used in various types of medical applications. Heating is one of the most important concerns in the neural tissue when illuminated with NIR light. Rodent models are frequently used to study laser-tissue interactions. As a part of ongoing research project in the neural interface laboratory, direct measurements of temperature in the rat brain cortex as a response to a pulsed sequence of NIR laser beam are available. In this thesis, finite element modeling approach is used to model and simulate the temperature elevation in neural tissue under the effect of NIR laser pulsing. Steady …

Effect Of Scan Time On Resting State Parameters, Dhruti Patel

Theses

In the past decade the interest in studying the spontaneous low-frequency fluctuations (LFF) in a resting-state brain has steadily grown. By measuring LFF (< 0.08 Hz) in blood-oxygen-level-dependent (BOLD) signals, resting-state functional magnetic resonance imaging (rs-fMRI) has proven to be a powerful tool in exploring brain network connectivity and functionality. Rs-fMRI data can be used to organize the brain into resting state networks (RSNs). In this thesis, rs-fMRI data are used to determine the minimum data acquisition time necessary to detect local intrinsic brain activity as a function of both the amplitude of low frequency fluctuations (ALFF) and the fractional amplitude of low frequency fluctuations (fALFF) in BOLD signals in healthy subjects. The data are obtained from 22 healthy subjects to use as a baseline for future rs-fMRI analysis. Voxel-wise analysis is performed on the whole brain, gray matter volume, and two previously established RSNs: the default mode network (DMN) and the visual system network, for all the subjects in this study.

Pearson’s correlation coefficients (r-values) are calculated from each subject. The entire time series for one subject is divided into 31 subsections and the r-values are calculated between each consecutive subsection in a subject. In total, there are 30 r- values. To better understand what the results mean across subjects and within subjects Fisher transformations are applied to the 30 calculated r-values for each subject to get a normal z-distribution. The mean across 22 subjects’ z-values is …

Brain Computer Interface Based Neurorehabilitation Technique Using A Commercially Available Eeg Headset, Abhineet Mishra

Theses

Neurorehabilitation has recently been augmented with the use of virtual reality and rehabilitation robotics. In many systems, some known volitional control must exist in order to synchronize the user intended movement with the therapeutic virtual or robotic movement. Brain Computer Interface (BCI) aims to open up a new rehabilitation option for clinical population having no residual movement due to disease or injury to the central or peripheral nervous system. Brain activity contains a wide variety of electrical signals which can be acquired using many invasive and non-invasive acquisition techniques and holds the potential to be used as an input to …